He was rushed to a general hospital in the city where doctors found a 5-centimeter hole in his stomach and took him to surgery before placing him in intensive care. He has now been transferred to a general ward. The hospital's medical staff believes he may have consumed liquid nitrogen in the last mouthful of the treat.

Nitrogen, with a temperature of minus 200 C, is injected into this kind of treat. The boy is believed to have consumed residual liquefied nitrogen at the bottom of the cup after some nitrogen appeared to have melted, they said.

Consuming liquefied nitrogen can deal lethal damage to internal organs.

A health official at the city's Southeastern Ward office said it has asked police to investigate the case following the tipoff from the boy's family.

The police are investigating the owner of the eatery on suspicions of professional negligence resulting in injury after the boy's parents filed a complaint. The eatery, which is now closed, had been operating without a business license, they said.

During Friday's meeting, the prime minister also ordered the ministries of industry and environment as well as the Ministry of Food and Drug Safety to examine child-related safety issues and come up with measures to strengthen children's food security. (Yonhap)